灌浆料流变性能的时变特性与屈服应力演化模型  

Time-dependent characteristics of rheological properties and yield stress evolution of grouting materials

作　　者：刘建祥[1] 赵唯坚 孙博超 江天任 王清民 Liu Jianxiang;Zhao Wejian;Sun Bochao;Jiang Tianren;Wang Qingmin(Zhejiang University,Hangzhou 310058,China)

机构地区：[1]浙江大学,浙江杭州310058

出　　处：《土木工程学报》2024年第5期27-40,共14页China Civil Engineering Journal

基　　金：国家自然科学基金(52108254);浙江大学科研项目(XY2022029)和浙江大学平衡建筑研究中心研发计划(K-20203512-15C)。

摘　　要：为研究灌浆料流变性能的时变特性,厘清流变性能随时间变化的机理,通过流变试验研究灌浆料的流变模型和流变参数随时间的变化规律。结合灌浆料的冷冻扫描电镜微观结构随时间的变化过程和流体力学理论,研究屈服应力的时变机理,并建立考虑絮凝效应、水化反应和骨料颗粒-水泥浆体相互作用三者共同影响的新屈服应力演化模型。结果表明:灌浆料的流变模型符合Herschel-Bulkley模型,屈服应力随时间增加而增加。水化产物在网状絮凝结构上不断堆积,网状絮凝结构逐渐变大,这不仅增强了水泥浆体的抗剪切能力,也导致浆体表现更高的黏度,使得骨料颗粒-水泥浆体的相互作用力增大。因此,灌浆料的屈服应力增大。提出的新屈服应力演化模型能更好地描述含骨料颗粒水泥基材料的屈服应力随时间的变化规律。研究结果可为灌浆料的流动扩散研究和深入理解水泥基材料流变性能的时变性提供理论基础。To investigate the time-dependent rheological properties of grouting materials and clarify the mechanism of rheological behavior changing over time,the rheological model and rheological parameters of the grouting materials were studied through rheological experiments to reveal their variations with time.By combining the evolution of the microstructure of the grouting slurry observed through cryo-scanning electron microscopy with fluid mechanics theory,the time-dependent mechanism of yield stress was investigated.A new yield stress evolution model was established considering the combined effects of the flocculation effect,hydration reaction,and the interaction between aggregates and cement paste.The results show that the rheological model of grouting material conforms to the Herschel-Bulkley model,and the yield stress increases over time.The hydration products accumulate gradually on the network flocculation structures,which results in enhancement of the shear resistance and increase in the viscosity of the cement paste,thereby increasing the interaction force between the aggregate particles and cement paste.Therefore,the yield stress of the grouting slurry increases over time.The proposed new yield stress evolution model can better describe the time-dependent behavior of the yield stress of cement-based materials containing aggregate particles.The research results can provide a theoretical basis for the study of the flow and diffusion of grouting slurry and a deeper understanding of the time-dependent rheological behavior of cementitious materials.

关 键 词：灌浆料 流变性能 屈服应力 水化产物 网状絮凝结构 

分 类 号：TU528.53[建筑科学—建筑技术科学]